Deep Substrate Bed - Denitrification
I've recently been spending a lot of time researching saltwater reef systems. In a reef tank it is general practice to have a sump with a refugium. Often times the main display tank or the refugium will have a deep sand bed of 4+ inches for the purposes of denitrification.
If one were to establish a deep substrate bed in a freshwater tank, would the same or similar anerobic bacteria form?
Do the lower oxygen levels have a negative effect on the roots? Or will the roots just not grow at this level anyway?
Would a system like this benefit from a black worm or snail population to turn the substrate?
I would like to take this approach with my next tank.